1. Field of the Invention
The present invention relates to a bending machine die provided with a vise for clamping an elongated workpiece to be bent.
2. Description of Related Art
A vise close to that one described below is produced by Jesse Engineering in Tacoma, Wash. (USA). The vise of Jesse Engineering is installed by a support member on the top of a die of a bending machine. Such a support member frontally holds a pivoting axis located above a die groove. A jaw is mounted swinging about this pivoting axis. The clamping portion of the jaw is under the pivoting axis, and above the latter there is a connection to the rod of a hydraulic cylinder mounted behind on the same support member of the jaw.
A clamping vise of the type above mentioned is certainly effective for elongated workpieces, also called tubes below, that are a small diameter and then capable of being deformed by a low deformation work.
However, if one considers that what retains a tube in the die groove is the cylinder rod urging on the jaw, it should be understood that it is only the hydraulic cylinder to counteract an opening of the same jaw. Actually, the hydraulic cylinder chosen by Jesse Engineering is not small and occupies great space in the working zone of the bending machine.
The present invention aims to overcome these drawbacks.